It is well known in the art of packaging to provide cushioning members or materials in the form of corrugated cardboard along with strips of paper folded in a zigzag or accordion manner. Typical examples are shown in U.S. Pat. Nos. 987,958 issued Mar. 28, 1911; 2,742,219 issued on Apr. 17, 1956; and 2,978,163 issued on Apr. 4, 1961.
While the foregoing types of cushioning are all made of paper or cardboard and thus are relatively inexpensive, they do not really provide a true "spring" in the sense of a metal type compression spring. The zigzag or accordion type folded paper strip or even cardboard strip while serving as a space filler is in a sense "frangible" in that once it is subjected to a large load, it will tend to remain collapsed rather than spring back to its initial configuration. While some spring-back, of course, occurs depending primarily on the thickness of the paper initially employed in forming the spring, a tendency results for the various folds to collapse more and more, the more persistent a load is provided thereon. In other words, a single fold in a strip of paper tends to crease and really not offer the desired resistance to movement. As a consequence, once one or more such accordion type pleats are smashed or collapsed, they tend to stay in such position and thus not function in a continuous manner to provide appropriate cushioning. The problem is particularly aggravated when packages are subjected to bumps and the like over prolonged periods of time such as in cross-country shipping in trucks.